NucleoL476 LR1121 Board Not Switching to Class B Despite Configuration

I'm currently working on a project involving the NucleoL476 LR1121 board, aiming to operate it in Class B mode. I have verified that the beacon is successfully transmitted by the gateway, and I have configured my network server (TTN) to use Class B. However, despite these configurations, I'm unable to see the device switch to this mode.

My Gateway (_globalconf.json):

TTN Configuration:

Device Details:

Board: NucleoL476 LR1121
Firmware/Software Version: v4.3.0

Reproduction Steps

Verified beacon transmission from the gateway:

Mar 15 14:59:39 os lora_pkt_fwd[129114]: ### [JIT] ###
Mar 15 14:59:39 os lora_pkt_fwd[129114]: src/jitqueue.c:444:jit_print_queue(): INFO: [jit] queue contains 3 beacons:
Mar 15 14:59:39 os lora_pkt_fwd[129114]: src/jitqueue.c:448:jit_print_queue():  - node[0]: count_us=2765857177 - type=3
Mar 15 14:59:39 os lora_pkt_fwd[129114]: src/jitqueue.c:448:jit_print_queue():  - node[1]: count_us=2893857580 - type=3
Mar 15 14:59:39 os lora_pkt_fwd[129114]: src/jitqueue.c:448:jit_print_queue():  - node[2]: count_us=3021857597 - type=3
Mar 15 15:00:39 os lora_pkt_fwd[129114]: ### SX1302 Status ###
Mar 15 15:00:39 os lora_pkt_fwd[129114]: # BEACON queued: 24
Mar 15 15:00:39 os lora_pkt_fwd[129114]: # BEACON sent so far: 21
Mar 15 15:00:39 os lora_pkt_fwd[129114]: # BEACON rejected: 0
Mar 15 15:00:39 os lora_pkt_fwd[129114]: INFO: Beacon dequeued (count_us=2765857177)
Mar 15 15:00:39 os lora_pkt_fwd[129114]: INFO: Beacon queued (count_us=3149857230, freq_hz=869525000, size=17):
Mar 15 15:01:12 os lora_pkt_fwd[129114]: ### SX1302 Status ###
Mar 15 15:01:12 os lora_pkt_fwd[129114]: # BEACON queued: 25
Mar 15 15:01:12 os lora_pkt_fwd[129114]: # BEACON sent so far: 22
Mar 15 15:01:12 os lora_pkt_fwd[129114]: # BEACON rejected: 0
Mar 15 15:02:09 os lora_pkt_fwd[129114]: ### SX1302 Status ###
Mar 15 15:02:09 os lora_pkt_fwd[129114]: # BEACON queued: 25
Mar 15 15:02:09 os lora_pkt_fwd[129114]: # BEACON sent so far: 22
Mar 15 15:02:09 os lora_pkt_fwd[129114]: # BEACON rejected: 0

Configured TTN for Class B operation as per screenshots.

Compiled the project with the following command:

make -C lbm_examples full_lr1110 MODEM_APP=PERIODICAL_UPLINK LBM_CLASS_B=yes

Expected Behavior

The device should switch to Class B mode, allowing for scheduled receive windows in addition to Class A's random receive windows.

Actual Behavior

The device does not switch to Class B mode. No indication of Class B operation or scheduled receive windows observed.

Request for Assistance

I am seeking guidance on how to properly configure my setup for Class B operation or if there are any known issues or additional steps required for the NucleoL476 LR1121 board to operate in Class B with TTN.

Thank you in advance for your support and assistance.

Lora-net / SWL2001